let luohuaCanvans = (obj) => {
	let sakura_point_vsh = `
	  uniform mat4 uProjection;
	  uniform mat4 uModelview;
	  uniform vec3 uResolution;
	  uniform vec3 uOffset;
	  uniform vec3 uDOF;  //x:focus distance, y:focus radius, z:max radius
	  uniform vec3 uFade; //x:start distance, y:half distance, z:near fade start

	  attribute vec3 aPosition;
	  attribute vec3 aEuler;
	  attribute vec2 aMisc; //x:size, y:fade

	  varying vec3 pposition;
	  varying float psize;
	  varying float palpha;
	  varying float pdist;

	  //varying mat3 rotMat;
	  varying vec3 normX;
	  varying vec3 normY;
	  varying vec3 normZ;
	  varying vec3 normal;

	  varying float diffuse;
	  varying float specular;
	  varying float rstop;
	  varying float distancefade;

	  void main(void) {
		  // Projection is based on vertical angle
		  vec4 pos = uModelview * vec4(aPosition + uOffset, 1.0);
		  gl_Position = uProjection * pos;
		  gl_PointSize = aMisc.x * uProjection[1][1] / -pos.z * uResolution.y * 0.5;
		  
		  pposition = pos.xyz;
		  psize = aMisc.x;
		  pdist = length(pos.xyz);
		  palpha = smoothstep(0.0, 1.0, (pdist - 0.1) / uFade.z);
		  
		  vec3 elrsn = sin(aEuler);
		  vec3 elrcs = cos(aEuler);
		  mat3 rotx = mat3(
			  1.0, 0.0, 0.0,
			  0.0, elrcs.x, elrsn.x,
			  0.0, -elrsn.x, elrcs.x
		  );
		  mat3 roty = mat3(
			  elrcs.y, 0.0, -elrsn.y,
			  0.0, 1.0, 0.0,
			  elrsn.y, 0.0, elrcs.y
		  );
		  mat3 rotz = mat3(
			  elrcs.z, elrsn.z, 0.0, 
			  -elrsn.z, elrcs.z, 0.0,
			  0.0, 0.0, 1.0
		  );
		  mat3 rotmat = rotx * roty * rotz;
		  normal = rotmat[2];
		  
		  mat3 trrotm = mat3(
			  rotmat[0][0], rotmat[1][0], rotmat[2][0],
			  rotmat[0][1], rotmat[1][1], rotmat[2][1],
			  rotmat[0][2], rotmat[1][2], rotmat[2][2]
		  );
		  normX = trrotm[0];
		  normY = trrotm[1];
		  normZ = trrotm[2];
		  
		  const vec3 lit = vec3(0.6917144638660746, 0.6917144638660746, -0.20751433915982237);
		  
		  float tmpdfs = dot(lit, normal);
		  if(tmpdfs < 0.0) {
			  normal = -normal;
			  tmpdfs = dot(lit, normal);
		  }
		  diffuse = 0.4 + tmpdfs;
		  
		  vec3 eyev = normalize(-pos.xyz);
		  if(dot(eyev, normal) > 0.0) {
			  vec3 hv = normalize(eyev + lit);
			  specular = pow(max(dot(hv, normal), 0.0), 20.0);
		  }
		  else {
			  specular = 0.0;
		  }
		  
		  rstop = clamp((abs(pdist - uDOF.x) - uDOF.y) / uDOF.z, 0.0, 1.0);
		  rstop = pow(rstop, 0.5);
		  //-0.69315 = ln(0.5)
		  distancefade = min(1.0, exp((uFade.x - pdist) * 0.69315 / uFade.y));
	  }`;
	let sakura_point_fsh = `
	  #ifdef GL_ES
	  //precision mediump float;
	  precision highp float;
	  #endif

	  uniform vec3 uDOF;  //x:focus distance, y:focus radius, z:max radius
	  uniform vec3 uFade; //x:start distance, y:half distance, z:near fade start

	  const vec3 fadeCol = vec3(0.08, 0.03, 0.06);

	  varying vec3 pposition;
	  varying float psize;
	  varying float palpha;
	  varying float pdist;

	  //varying mat3 rotMat;
	  varying vec3 normX;
	  varying vec3 normY;
	  varying vec3 normZ;
	  varying vec3 normal;

	  varying float diffuse;
	  varying float specular;
	  varying float rstop;
	  varying float distancefade;

	  float ellipse(vec2 p, vec2 o, vec2 r) {
		  vec2 lp = (p - o) / r;
		  return length(lp) - 1.0;
	  }

	  void main(void) {
		  vec3 p = vec3(gl_PointCoord - vec2(0.5, 0.5), 0.0) * 2.0;
		  vec3 d = vec3(0.0, 0.0, -1.0);
		  float nd = normZ.z; //dot(-normZ, d);
		  if(abs(nd) < 0.0001) discard;
		  
		  float np = dot(normZ, p);
		  vec3 tp = p + d * np / nd;
		  vec2 coord = vec2(dot(normX, tp), dot(normY, tp));
		  
		  //angle = 15 degree
		  const float flwrsn = 0.258819045102521;
		  const float flwrcs = 0.965925826289068;
		  mat2 flwrm = mat2(flwrcs, -flwrsn, flwrsn, flwrcs);
		  vec2 flwrp = vec2(abs(coord.x), coord.y) * flwrm;
		  
		  float r;
		  if(flwrp.x < 0.0) {
			  r = ellipse(flwrp, vec2(0.065, 0.024) * 0.5, vec2(0.36, 0.96) * 0.5);
		  }
		  else {
			  r = ellipse(flwrp, vec2(0.065, 0.024) * 0.5, vec2(0.58, 0.96) * 0.5);
		  }
		  
		  if(r > rstop) discard;
		  
		  vec3 col = mix(vec3(1.0, 0.8, 0.75), vec3(1.0, 0.9, 0.87), r);
		  float grady = mix(0.0, 1.0, pow(coord.y * 0.5 + 0.5, 0.35));
		  col *= vec3(1.0, grady, grady);
		  col *= mix(0.8, 1.0, pow(abs(coord.x), 0.3));
		  col = col * diffuse + specular;
		  
		  col = mix(fadeCol, col, distancefade);
		  
		  float alpha = (rstop > 0.001)? (0.5 - r / (rstop * 2.0)) : 1.0;
		  alpha = smoothstep(0.0, 1.0, alpha) * palpha;
		  
		  gl_FragColor = vec4(col * 0.5, alpha);
	  }`;
	let fx_common_vsh = `
	  uniform vec3 uResolution;
	  attribute vec2 aPosition;

	  varying vec2 texCoord;
	  varying vec2 screenCoord;

	  void main(void) {
		  gl_Position = vec4(aPosition, 0.0, 1.0);
		  texCoord = aPosition.xy * 0.5 + vec2(0.5, 0.5);
		  screenCoord = aPosition.xy * vec2(uResolution.z, 1.0);
	  }`;
	let bg_fsh = `
	  #ifdef GL_ES
	  //precision mediump float;
	  precision highp float;
	  #endif

	  uniform vec2 uTimes;

	  varying vec2 texCoord;
	  varying vec2 screenCoord;

	  void main(void) {
		  vec3 col;
		  float c;
		  vec2 tmpv = texCoord * vec2(0.8, 1.0) - vec2(0.95, 1.0);
		  c = exp(-pow(length(tmpv) * 1.8, 2.0));
		  col = mix(vec3(0.02, 0.0, 0.03), vec3(0.96, 0.98, 1.0) * 1.5, c);
		  gl_FragColor = vec4(col * 0.5, 1.0);
	  }`;
	let fx_brightbuf_fsh = `
	  #ifdef GL_ES
	  //precision mediump float;
	  precision highp float;
	  #endif
	  uniform sampler2D uSrc;
	  uniform vec2 uDelta;

	  varying vec2 texCoord;
	  varying vec2 screenCoord;

	  void main(void) {
		  vec4 col = texture2D(uSrc, texCoord);
		  gl_FragColor = vec4(col.rgb * 2.0 - vec3(0.5), 1.0);
	  }`;
	let fx_dirblur_r4_fsh = `
	  #ifdef GL_ES
	  //precision mediump float;
	  precision highp float;
	  #endif
	  uniform sampler2D uSrc;
	  uniform vec2 uDelta;
	  uniform vec4 uBlurDir; //dir(x, y), stride(z, w)

	  varying vec2 texCoord;
	  varying vec2 screenCoord;

	  void main(void) {
		  vec4 col = texture2D(uSrc, texCoord);
		  col = col + texture2D(uSrc, texCoord + uBlurDir.xy * uDelta);
		  col = col + texture2D(uSrc, texCoord - uBlurDir.xy * uDelta);
		  col = col + texture2D(uSrc, texCoord + (uBlurDir.xy + uBlurDir.zw) * uDelta);
		  col = col + texture2D(uSrc, texCoord - (uBlurDir.xy + uBlurDir.zw) * uDelta);
		  gl_FragColor = col / 5.0;
	  }`;
	let pp_final_vsh = `
	  uniform vec3 uResolution;
	  attribute vec2 aPosition;
	  varying vec2 texCoord;
	  varying vec2 screenCoord;
	  void main(void) {
		  gl_Position = vec4(aPosition, 0.0, 1.0);
		  texCoord = aPosition.xy * 0.5 + vec2(0.5, 0.5);
		  screenCoord = aPosition.xy * vec2(uResolution.z, 1.0);
	  }`;
	let pp_final_fsh = `
	  #ifdef GL_ES
	  //precision mediump float;
	  precision highp float;
	  #endif
	  uniform sampler2D uSrc;
	  uniform sampler2D uBloom;
	  uniform vec2 uDelta;
	  varying vec2 texCoord;
	  varying vec2 screenCoord;
	  void main(void) {
		  vec4 srccol = texture2D(uSrc, texCoord) * 2.0;
		  vec4 bloomcol = texture2D(uBloom, texCoord);
		  vec4 col;
		  col = srccol + bloomcol * (vec4(1.0) + srccol);
		  col *= smoothstep(1.0, 0.0, pow(length((texCoord - vec2(0.5)) * 2.0), 1.2) * 0.5);
		  col = pow(col, vec4(0.45454545454545)); //(1.0 / 2.2)
		  
		  gl_FragColor = vec4(col.rgb, 1.0);
		  gl_FragColor.a = 1.0;
	  }`;

	// Utilities
	var Vector3 = {};
	var Matrix44 = {};
	Vector3.create = function(x, y, z) {
		return {
			x: x,
			y: y,
			z: z
		};
	};
	Vector3.dot = function(v0, v1) {
		return v0.x * v1.x + v0.y * v1.y + v0.z * v1.z;
	};
	Vector3.cross = function(v, v0, v1) {
		v.x = v0.y * v1.z - v0.z * v1.y;
		v.y = v0.z * v1.x - v0.x * v1.z;
		v.z = v0.x * v1.y - v0.y * v1.x;
	};
	Vector3.normalize = function(v) {
		var l = v.x * v.x + v.y * v.y + v.z * v.z;
		if (l > 0.00001) {
			l = 1.0 / Math.sqrt(l);
			v.x *= l;
			v.y *= l;
			v.z *= l;
		}
	};
	Vector3.arrayForm = function(v) {
		if (v.array) {
			v.array[0] = v.x;
			v.array[1] = v.y;
			v.array[2] = v.z;
		} else {
			v.array = new Float32Array([v.x, v.y, v.z]);
		}
		return v.array;
	};
	Matrix44.createIdentity = function() {
		return new Float32Array([
			1.0,
			0.0,
			0.0,
			0.0,
			0.0,
			1.0,
			0.0,
			0.0,
			0.0,
			0.0,
			1.0,
			0.0,
			0.0,
			0.0,
			0.0,
			1.0
		]);
	};
	Matrix44.loadProjection = function(
		m,
		aspect,
		vdeg,
		near,
		far
	) {
		let h = near * Math.tan(((vdeg * Math.PI) / 180.0) * 0.5) * 2.0;
		let w = h * aspect;

		m[0] = (2.0 * near) / w;
		m[1] = 0.0;
		m[2] = 0.0;
		m[3] = 0.0;

		m[4] = 0.0;
		m[5] = (2.0 * near) / h;
		m[6] = 0.0;
		m[7] = 0.0;

		m[8] = 0.0;
		m[9] = 0.0;
		m[10] = -(far + near) / (far - near);
		m[11] = -1.0;

		m[12] = 0.0;
		m[13] = 0.0;
		m[14] = (-2.0 * far * near) / (far - near);
		m[15] = 0.0;
	};
	Matrix44.loadLookAt = function(m, vpos, vlook, vup) {
		let frontv = Vector3.create(
			vpos.x - vlook.x,
			vpos.y - vlook.y,
			vpos.z - vlook.z
		);
		Vector3.normalize(frontv);
		let sidev = Vector3.create(1.0, 0.0, 0.0);
		Vector3.cross(sidev, vup, frontv);
		Vector3.normalize(sidev);
		let topv = Vector3.create(1.0, 0.0, 0.0);
		Vector3.cross(topv, frontv, sidev);
		Vector3.normalize(topv);

		m[0] = sidev.x;
		m[1] = topv.x;
		m[2] = frontv.x;
		m[3] = 0.0;

		m[4] = sidev.y;
		m[5] = topv.y;
		m[6] = frontv.y;
		m[7] = 0.0;

		m[8] = sidev.z;
		m[9] = topv.z;
		m[10] = frontv.z;
		m[11] = 0.0;

		m[12] = -(vpos.x * m[0] + vpos.y * m[4] + vpos.z * m[8]);
		m[13] = -(vpos.x * m[1] + vpos.y * m[5] + vpos.z * m[9]);
		m[14] = -(vpos.x * m[2] + vpos.y * m[6] + vpos.z * m[10]);
		m[15] = 1.0;
	};

	//
	var timeInfo = {
		start: 0,
		prev: 0, // Date
		delta: 0,
		elapsed: 0 // Number(sec)
	};

	//
	var gl;
	var renderSpec = {
		width: 0,
		height: 0,
		aspect: 1,
		array: new Float32Array(3),
		halfWidth: 0,
		halfHeight: 0,
		halfArray: new Float32Array(3)
		// and some render targets. see setViewport()
	};
	renderSpec.setSize = function(w, h) {
		renderSpec.width = w;
		renderSpec.height = h;
		renderSpec.aspect = renderSpec.width / renderSpec.height;
		renderSpec.array[0] = renderSpec.width;
		renderSpec.array[1] = renderSpec.height;
		renderSpec.array[2] = renderSpec.aspect;

		renderSpec.halfWidth = Math.floor(w / 2);
		renderSpec.halfHeight = Math.floor(h / 2);
		renderSpec.halfArray[0] = renderSpec.halfWidth;
		renderSpec.halfArray[1] = renderSpec.halfHeight;
		renderSpec.halfArray[2] = renderSpec.halfWidth / renderSpec.halfHeight;
	};

	function deleteRenderTarget(rt) {
		gl.deleteFramebuffer(rt.frameBuffer);
		gl.deleteRenderbuffer(rt.renderBuffer);
		gl.deleteTexture(rt.texture);
	}

	function createRenderTarget(w, h) {
		var ret = {
			width: w,
			height: h,
			sizeArray: new Float32Array([w, h, w / h]),
			dtxArray: new Float32Array([1.0 / w, 1.0 / h])
		};
		ret.frameBuffer = gl.createFramebuffer();
		ret.renderBuffer = gl.createRenderbuffer();
		ret.texture = gl.createTexture();

		gl.bindTexture(gl.TEXTURE_2D, ret.texture);
		gl.texImage2D(
			gl.TEXTURE_2D,
			0,
			gl.RGBA,
			w,
			h,
			0,
			gl.RGBA,
			gl.UNSIGNED_BYTE,
			null
		);
		gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
		gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
		gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
		gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);

		gl.bindFramebuffer(gl.FRAMEBUFFER, ret.frameBuffer);
		gl.framebufferTexture2D(
			gl.FRAMEBUFFER,
			gl.COLOR_ATTACHMENT0,
			gl.TEXTURE_2D,
			ret.texture,
			0
		);

		gl.bindRenderbuffer(gl.RENDERBUFFER, ret.renderBuffer);
		gl.renderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_COMPONENT16, w, h);
		gl.framebufferRenderbuffer(
			gl.FRAMEBUFFER,
			gl.DEPTH_ATTACHMENT,
			gl.RENDERBUFFER,
			ret.renderBuffer
		);

		gl.bindTexture(gl.TEXTURE_2D, null);
		gl.bindRenderbuffer(gl.RENDERBUFFER, null);
		gl.bindFramebuffer(gl.FRAMEBUFFER, null);

		return ret;
	}

	function compileShader(shtype, shsrc) {
		var retsh = gl.createShader(shtype);

		gl.shaderSource(retsh, shsrc);
		gl.compileShader(retsh);

		if (!gl.getShaderParameter(retsh, gl.COMPILE_STATUS)) {
			var errlog = gl.getShaderInfoLog(retsh);
			gl.deleteShader(retsh);
			console.error(errlog);
			return null;
		}
		return retsh;
	}

	function createShader(
		vtxsrc,
		frgsrc,
		uniformlist,
		attrlist
	) {
		var vsh = compileShader(gl.VERTEX_SHADER, vtxsrc);
		var fsh = compileShader(gl.FRAGMENT_SHADER, frgsrc);

		if (vsh == null || fsh == null) {
			return null;
		}

		var prog = gl.createProgram();
		gl.attachShader(prog, vsh);
		gl.attachShader(prog, fsh);

		gl.deleteShader(vsh);
		gl.deleteShader(fsh);

		gl.linkProgram(prog);
		if (!gl.getProgramParameter(prog, gl.LINK_STATUS)) {
			var errlog = gl.getProgramInfoLog(prog);
			console.error(errlog);
			return null;
		}

		if (uniformlist) {
			prog.uniforms = {};
			for (var i = 0; i < uniformlist.length; i++) {
				prog.uniforms[uniformlist[i]] = gl.getUniformLocation(
					prog,
					uniformlist[i]
				);
			}
		}

		if (attrlist) {
			prog.attributes = {};
			for (let i = 0; i < attrlist.length; i++) {
				let attr = attrlist[i];
				prog.attributes[attr] = gl.getAttribLocation(prog, attr);
			}
		}

		return prog;
	}

	function useShader(prog) {
		gl.useProgram(prog);
		for (let attr in prog.attributes) {
			gl.enableVertexAttribArray(prog.attributes[attr]);
		}
	}

	function unuseShader(prog) {
		for (let attr in prog.attributes) {
			gl.disableVertexAttribArray(prog.attributes[attr]);
		}
		gl.useProgram(null);
	}

	/////
	var projection = {
		angle: 60,
		nearfar: new Float32Array([0.1, 100.0]),
		matrix: Matrix44.createIdentity()
	};
	var camera = {
		position: Vector3.create(0, 0, 100),
		lookat: Vector3.create(0, 0, 0),
		up: Vector3.create(0, 1, 0),
		dof: Vector3.create(10.0, 4.0, 8.0),
		matrix: Matrix44.createIdentity()
	};

	var pointFlower = {};
	// var meshFlower = {};
	var sceneStandBy = false;

	var BlossomParticle = function() {
		this.velocity = new Array(3);
		this.rotation = new Array(3);
		this.position = new Array(3);
		this.euler = new Array(3);
		this.size = 1.0;
		this.alpha = 1.0;
		this.zkey = 0.0;
	};

	BlossomParticle.prototype.setVelocity = function(
		vx,
		vy,
		vz
	) {
		this.velocity[0] = vx;
		this.velocity[1] = vy;
		this.velocity[2] = vz;
	};

	BlossomParticle.prototype.setRotation = function(
		rx,
		ry,
		rz
	) {
		this.rotation[0] = rx;
		this.rotation[1] = ry;
		this.rotation[2] = rz;
	};

	BlossomParticle.prototype.setPosition = function(
		nx,
		ny,
		nz
	) {
		this.position[0] = nx;
		this.position[1] = ny;
		this.position[2] = nz;
	};

	BlossomParticle.prototype.setEulerAngles = function(
		rx,
		ry,
		rz
	) {
		this.euler[0] = rx;
		this.euler[1] = ry;
		this.euler[2] = rz;
	};

	BlossomParticle.prototype.setSize = function(s) {
		this.size = s;
	};

	BlossomParticle.prototype.update = function(dt, et) {
		this.position[0] += this.velocity[0] * dt;
		this.position[1] += this.velocity[1] * dt;
		this.position[2] += this.velocity[2] * dt;

		this.euler[0] += this.rotation[0] * dt;
		this.euler[1] += this.rotation[1] * dt;
		this.euler[2] += this.rotation[2] * dt;
	};

	function createPointFlowers() {
		// get point sizes
		var prm = gl.getParameter(gl.ALIASED_POINT_SIZE_RANGE);
		renderSpec.pointSize = {
			min: prm[0],
			max: prm[1]
		};

		var vtxsrc = sakura_point_vsh;
		var frgsrc = sakura_point_fsh;

		pointFlower.program = createShader(
			vtxsrc,
			frgsrc, [
				"uProjection",
				"uModelview",
				"uResolution",
				"uOffset",
				"uDOF",
				"uFade"
			], ["aPosition", "aEuler", "aMisc"]
		);

		useShader(pointFlower.program);
		pointFlower.offset = new Float32Array([0.0, 0.0, 0.0]);
		pointFlower.fader = Vector3.create(0.0, 10.0, 0.0);

		// paramerters: velocity[3], rotate[3]
		pointFlower.numFlowers = 1600;
		pointFlower.particles = new Array(pointFlower.numFlowers);
		// vertex attributes {position[3], euler_xyz[3], size[1]}
		pointFlower.dataArray = new Float32Array(
			pointFlower.numFlowers * (3 + 3 + 2)
		);
		pointFlower.positionArrayOffset = 0;
		pointFlower.eulerArrayOffset = pointFlower.numFlowers * 3;
		pointFlower.miscArrayOffset = pointFlower.numFlowers * 6;

		pointFlower.buffer = gl.createBuffer();
		gl.bindBuffer(gl.ARRAY_BUFFER, pointFlower.buffer);
		gl.bufferData(gl.ARRAY_BUFFER, pointFlower.dataArray, gl.DYNAMIC_DRAW);
		gl.bindBuffer(gl.ARRAY_BUFFER, null);

		unuseShader(pointFlower.program);

		for (let i = 0; i < pointFlower.numFlowers; i++) {
			pointFlower.particles[i] = new BlossomParticle();
		}
	}

	function initPointFlowers() {
		//area
		pointFlower.area = Vector3.create(20.0, 20.0, 20.0);
		pointFlower.area.x = pointFlower.area.y * renderSpec.aspect;

		pointFlower.fader.x = 10.0; //env fade start
		pointFlower.fader.y = pointFlower.area.z; //env fade half
		pointFlower.fader.z = 0.1; //near fade start

		//particles
		var PI2 = Math.PI * 2.0;
		var tmpv3 = Vector3.create(0, 0, 0);
		var tmpv = 0;
		var symmetryrand = function() {
			return Math.random() * 2.0 - 1.0;
		};
		for (let i = 0; i < pointFlower.numFlowers; i++) {
			let tmpprtcl = pointFlower.particles[i];

			//velocity
			tmpv3.x = symmetryrand() * 0.3 + 0.8;
			tmpv3.y = symmetryrand() * 0.2 - 1.0;
			tmpv3.z = symmetryrand() * 0.3 + 0.5;
			Vector3.normalize(tmpv3);
			tmpv = 2.0 + Math.random() * 1.0;
			tmpprtcl.setVelocity(tmpv3.x * tmpv, tmpv3.y * tmpv, tmpv3.z * tmpv);

			//rotation
			tmpprtcl.setRotation(
				symmetryrand() * PI2 * 0.5,
				symmetryrand() * PI2 * 0.5,
				symmetryrand() * PI2 * 0.5
			);

			//position
			tmpprtcl.setPosition(
				symmetryrand() * pointFlower.area.x,
				symmetryrand() * pointFlower.area.y,
				symmetryrand() * pointFlower.area.z
			);

			//euler
			tmpprtcl.setEulerAngles(
				Math.random() * Math.PI * 2.0,
				Math.random() * Math.PI * 2.0,
				Math.random() * Math.PI * 2.0
			);

			//size
			tmpprtcl.setSize(0.9 + Math.random() * 0.1);
		}
	}

	function renderPointFlowers() {
		//update
		var PI2 = Math.PI * 2.0;
		// var limit = [pointFlower.area.x, pointFlower.area.y, pointFlower.area.z];
		var repeatPos = function(prt, cmp, limit) {
			if (Math.abs(prt.position[cmp]) - prt.size * 0.5 > limit) {
				//out of area
				if (prt.position[cmp] > 0) {
					prt.position[cmp] -= limit * 2.0;
				} else {
					prt.position[cmp] += limit * 2.0;
				}
			}
		};
		var repeatEuler = function(prt, cmp) {
			prt.euler[cmp] = prt.euler[cmp] % PI2;
			if (prt.euler[cmp] < 0.0) {
				prt.euler[cmp] += PI2;
			}
		};

		for (let i = 0; i < pointFlower.numFlowers; i++) {
			let prtcl = pointFlower.particles[i];
			prtcl.update(timeInfo.delta, timeInfo.elapsed);
			repeatPos(prtcl, 0, pointFlower.area.x);
			repeatPos(prtcl, 1, pointFlower.area.y);
			repeatPos(prtcl, 2, pointFlower.area.z);
			repeatEuler(prtcl, 0);
			repeatEuler(prtcl, 1);
			repeatEuler(prtcl, 2);

			prtcl.alpha = 1.0; //(pointFlower.area.z - prtcl.position[2]) * 0.5;

			prtcl.zkey =
				camera.matrix[2] * prtcl.position[0] +
				camera.matrix[6] * prtcl.position[1] +
				camera.matrix[10] * prtcl.position[2] +
				camera.matrix[14];
		}

		// sort
		pointFlower.particles.sort(function(p0, p1) {
			return p0.zkey - p1.zkey;
		});

		// update data
		var ipos = pointFlower.positionArrayOffset;
		var ieuler = pointFlower.eulerArrayOffset;
		var imisc = pointFlower.miscArrayOffset;
		for (let i = 0; i < pointFlower.numFlowers; i++) {
			let prtcl = pointFlower.particles[i];
			pointFlower.dataArray[ipos] = prtcl.position[0];
			pointFlower.dataArray[ipos + 1] = prtcl.position[1];
			pointFlower.dataArray[ipos + 2] = prtcl.position[2];
			ipos += 3;
			pointFlower.dataArray[ieuler] = prtcl.euler[0];
			pointFlower.dataArray[ieuler + 1] = prtcl.euler[1];
			pointFlower.dataArray[ieuler + 2] = prtcl.euler[2];
			ieuler += 3;
			pointFlower.dataArray[imisc] = prtcl.size;
			pointFlower.dataArray[imisc + 1] = prtcl.alpha;
			imisc += 2;
		}

		//draw
		gl.enable(gl.BLEND);
		//gl.disable(gl.DEPTH_TEST);
		gl.blendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA);

		var prog = pointFlower.program;
		useShader(prog);

		gl.uniformMatrix4fv(prog.uniforms.uProjection, false, projection.matrix);
		gl.uniformMatrix4fv(prog.uniforms.uModelview, false, camera.matrix);
		gl.uniform3fv(prog.uniforms.uResolution, renderSpec.array);
		gl.uniform3fv(prog.uniforms.uDOF, Vector3.arrayForm(camera.dof));
		gl.uniform3fv(prog.uniforms.uFade, Vector3.arrayForm(pointFlower.fader));

		gl.bindBuffer(gl.ARRAY_BUFFER, pointFlower.buffer);
		gl.bufferData(gl.ARRAY_BUFFER, pointFlower.dataArray, gl.DYNAMIC_DRAW);

		gl.vertexAttribPointer(
			prog.attributes.aPosition,
			3,
			gl.FLOAT,
			false,
			0,
			pointFlower.positionArrayOffset * Float32Array.BYTES_PER_ELEMENT
		);
		gl.vertexAttribPointer(
			prog.attributes.aEuler,
			3,
			gl.FLOAT,
			false,
			0,
			pointFlower.eulerArrayOffset * Float32Array.BYTES_PER_ELEMENT
		);
		gl.vertexAttribPointer(
			prog.attributes.aMisc,
			2,
			gl.FLOAT,
			false,
			0,
			pointFlower.miscArrayOffset * Float32Array.BYTES_PER_ELEMENT
		);

		// doubler
		for (let i = 1; i < 2; i++) {
			let zpos = i * -2.0;
			pointFlower.offset[0] = pointFlower.area.x * -1.0;
			pointFlower.offset[1] = pointFlower.area.y * -1.0;
			pointFlower.offset[2] = pointFlower.area.z * zpos;
			gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
			gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);

			pointFlower.offset[0] = pointFlower.area.x * -1.0;
			pointFlower.offset[1] = pointFlower.area.y * 1.0;
			pointFlower.offset[2] = pointFlower.area.z * zpos;
			gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
			gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);

			pointFlower.offset[0] = pointFlower.area.x * 1.0;
			pointFlower.offset[1] = pointFlower.area.y * -1.0;
			pointFlower.offset[2] = pointFlower.area.z * zpos;
			gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
			gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);

			pointFlower.offset[0] = pointFlower.area.x * 1.0;
			pointFlower.offset[1] = pointFlower.area.y * 1.0;
			pointFlower.offset[2] = pointFlower.area.z * zpos;
			gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
			gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);
		}

		//main
		pointFlower.offset[0] = 0.0;
		pointFlower.offset[1] = 0.0;
		pointFlower.offset[2] = 0.0;
		gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
		gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);

		gl.bindBuffer(gl.ARRAY_BUFFER, null);
		unuseShader(prog);

		gl.enable(gl.DEPTH_TEST);
		gl.disable(gl.BLEND);
	}

	// effects
	//common util
	function createEffectProgram(
		vtxsrc,
		frgsrc,
		exunifs,
		exattrs
	) {
		var ret = {};
		var unifs = ["uResolution", "uSrc", "uDelta"];
		if (exunifs) {
			unifs = unifs.concat(exunifs);
		}
		var attrs = ["aPosition"];
		if (exattrs) {
			attrs = attrs.concat(exattrs);
		}

		ret.program = createShader(vtxsrc, frgsrc, unifs, attrs);
		useShader(ret.program);

		ret.dataArray = new Float32Array([-1.0, -1.0,
			1.0, -1.0, -1.0,
			1.0,
			1.0,
			1.0
		]);
		ret.buffer = gl.createBuffer();
		gl.bindBuffer(gl.ARRAY_BUFFER, ret.buffer);
		gl.bufferData(gl.ARRAY_BUFFER, ret.dataArray, gl.STATIC_DRAW);

		gl.bindBuffer(gl.ARRAY_BUFFER, null);
		unuseShader(ret.program);

		return ret;
	}

	// basic usage
	// useEffect(prog, srctex({'texture':texid, 'dtxArray':(f32)[dtx, dty]})); //basic initialize
	// gl.uniform**(...); //additional uniforms
	// drawEffect()
	// unuseEffect(prog)
	// TEXTURE0 makes src
	function useEffect(fxobj, srctex) {
		var prog = fxobj.program;
		useShader(prog);
		gl.uniform3fv(prog.uniforms.uResolution, renderSpec.array);

		if (srctex != null) {
			gl.uniform2fv(prog.uniforms.uDelta, srctex.dtxArray);
			gl.uniform1i(prog.uniforms.uSrc, 0);

			gl.activeTexture(gl.TEXTURE0);
			gl.bindTexture(gl.TEXTURE_2D, srctex.texture);
		}
	}

	function drawEffect(fxobj) {
		gl.bindBuffer(gl.ARRAY_BUFFER, fxobj.buffer);
		gl.vertexAttribPointer(
			fxobj.program.attributes.aPosition,
			2,
			gl.FLOAT,
			false,
			0,
			0
		);
		gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
	}

	function unuseEffect(fxobj) {
		unuseShader(fxobj.program);
	}

	var effectLib = {};

	function createEffectLib() {
		var vtxsrc, frgsrc;
		//common
		var cmnvtxsrc = fx_common_vsh;

		//background
		frgsrc = bg_fsh;
		effectLib.sceneBg = createEffectProgram(
			cmnvtxsrc,
			frgsrc, ["uTimes"],
			null
		);

		// make brightpixels buffer
		frgsrc = fx_brightbuf_fsh;
		effectLib.mkBrightBuf = createEffectProgram(
			cmnvtxsrc,
			frgsrc,
			null,
			null
		);

		// direction blur
		frgsrc = fx_dirblur_r4_fsh;
		effectLib.dirBlur = createEffectProgram(
			cmnvtxsrc,
			frgsrc, ["uBlurDir"],
			null
		);

		//final composite
		vtxsrc = pp_final_vsh;
		frgsrc = pp_final_fsh;
		// console.log('frgsrc :',frgsrc )
		effectLib.finalComp = createEffectProgram(
			vtxsrc,
			frgsrc, ["uBloom"],
			null
		);
	}

	// background
	function createBackground() {
		//console.log("create background");
	}

	function initBackground() {
		//console.log("init background");
	}

	function renderBackground() {
		gl.disable(gl.DEPTH_TEST);

		useEffect(effectLib.sceneBg, null);
		gl.uniform2f(
			effectLib.sceneBg.program.uniforms.uTimes,
			timeInfo.elapsed,
			timeInfo.delta
		);
		drawEffect(effectLib.sceneBg);
		unuseEffect(effectLib.sceneBg);

		gl.enable(gl.DEPTH_TEST);
	}

	// post process
	// var postProcess = {};
	function createPostProcess() {
		//console.log("create post process");
	}

	function initPostProcess() {
		//console.log("init post process");
	}

	function renderPostProcess() {
		gl.enable(gl.TEXTURE_2D);
		gl.disable(gl.DEPTH_TEST);
		var bindRT = function(rt, isclear) {
			gl.bindFramebuffer(gl.FRAMEBUFFER, rt.frameBuffer);
			gl.viewport(0, 0, rt.width, rt.height);
			if (isclear) {
				gl.clearColor(0, 0, 0, 0);
				gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
			}
		};

		//make bright buff
		bindRT(renderSpec.wHalfRT0, true);
		useEffect(effectLib.mkBrightBuf, renderSpec.mainRT);
		drawEffect(effectLib.mkBrightBuf);
		unuseEffect(effectLib.mkBrightBuf);

		// make bloom
		for (let i = 0; i < 2; i++) {
			let p = 1.5 + 1 * i;
			let s = 2.0 + 1 * i;
			bindRT(renderSpec.wHalfRT1, true);
			useEffect(effectLib.dirBlur, renderSpec.wHalfRT0);
			gl.uniform4f(
				effectLib.dirBlur.program.uniforms.uBlurDir,
				p,
				0.0,
				s,
				0.0
			);
			drawEffect(effectLib.dirBlur);
			unuseEffect(effectLib.dirBlur);

			bindRT(renderSpec.wHalfRT0, true);
			useEffect(effectLib.dirBlur, renderSpec.wHalfRT1);
			gl.uniform4f(
				effectLib.dirBlur.program.uniforms.uBlurDir,
				0.0,
				p,
				0.0,
				s
			);
			drawEffect(effectLib.dirBlur);
			unuseEffect(effectLib.dirBlur);
		}

		//display
		gl.bindFramebuffer(gl.FRAMEBUFFER, null);
		gl.viewport(0, 0, renderSpec.width, renderSpec.height);
		gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);

		useEffect(effectLib.finalComp, renderSpec.mainRT);
		gl.uniform1i(effectLib.finalComp.program.uniforms.uBloom, 1);
		gl.activeTexture(gl.TEXTURE1);
		gl.bindTexture(gl.TEXTURE_2D, renderSpec.wHalfRT0.texture);
		drawEffect(effectLib.finalComp);
		unuseEffect(effectLib.finalComp);

		gl.enable(gl.DEPTH_TEST);
	}

	/////
	// var SceneEnv = {};
	function createScene() {
		createEffectLib();
		createBackground();
		createPointFlowers();
		createPostProcess();
		sceneStandBy = true;
	}

	function initScene() {
		initBackground();
		initPointFlowers();
		initPostProcess();

		//camera.position.z = 17.320508;
		camera.position.z = pointFlower.area.z + projection.nearfar[0];
		projection.angle =
			((Math.atan2(
						pointFlower.area.y,
						camera.position.z + pointFlower.area.z
					) *
					180.0) /
				Math.PI) *
			2.0;
		Matrix44.loadProjection(
			projection.matrix,
			renderSpec.aspect,
			projection.angle,
			projection.nearfar[0],
			projection.nearfar[1]
		);
	}

	function renderScene() {
		//draw
		Matrix44.loadLookAt(
			camera.matrix,
			camera.position,
			camera.lookat,
			camera.up
		);

		gl.enable(gl.DEPTH_TEST);

		//gl.bindFramebuffer(gl.FRAMEBUFFER, null);
		gl.bindFramebuffer(gl.FRAMEBUFFER, renderSpec.mainRT.frameBuffer);
		gl.viewport(0, 0, renderSpec.mainRT.width, renderSpec.mainRT.height);
		gl.clearColor(0.005, 0, 0.05, 0);
		gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);

		renderBackground();
		renderPointFlowers();
		renderPostProcess();
	}

	/////
	function onResize(e) {
		makeCanvasFullScreen(document.getElementById("sakura"));
		setViewports();
		if (sceneStandBy) {
			initScene();
		}
	}

	function setViewports() {
		renderSpec.setSize(gl.canvas.width, gl.canvas.height);

		gl.clearColor(0.2, 0.2, 0.5, 1.0);
		gl.viewport(0, 0, renderSpec.width, renderSpec.height);

		var rtfunc = function(rtname, rtw, rth) {
			var rt = renderSpec[rtname];
			if (rt) deleteRenderTarget(rt);
			renderSpec[rtname] = createRenderTarget(rtw, rth);
		};
		rtfunc("mainRT", renderSpec.width, renderSpec.height);
		rtfunc("wFullRT0", renderSpec.width, renderSpec.height);
		rtfunc("wFullRT1", renderSpec.width, renderSpec.height);
		rtfunc("wHalfRT0", renderSpec.halfWidth, renderSpec.halfHeight);
		rtfunc("wHalfRT1", renderSpec.halfWidth, renderSpec.halfHeight);
	}

	function render() {
		renderScene();
	}

	var animating = true;

	function animate() {
		var curdate = new Date();
		timeInfo.elapsed = (curdate - timeInfo.start) / 1000.0;
		timeInfo.delta = (curdate - timeInfo.prev) / 1000.0;
		timeInfo.prev = curdate;

		if (animating) requestAnimationFrame(animate);
		render();
	}

	function makeCanvasFullScreen(canvas) {
		var b = document.body;
		var d = document.documentElement;
		let fullw = Math.max(
			b.clientWidth,
			b.scrollWidth,
			d.scrollWidth,
			d.clientWidth
		);
		let fullh = Math.max(
			b.clientHeight,
			b.scrollHeight,
			d.scrollHeight,
			d.clientHeight
		);
		canvas.width = fullw;
		canvas.height = fullh;
	}

	// 保证每次都执行
	var canvas = document.getElementById("sakura");
	try {
		makeCanvasFullScreen(canvas);
		gl = canvas.getContext("experimental-webgl");
	} catch (e) {
		alert("WebGL not supported." + e);
		console.error(e);
		return;
	}

	window.addEventListener("resize", onResize);

	setViewports();
	createScene();
	initScene();

	timeInfo.start = new Date();
	timeInfo.prev = timeInfo.start;
	animate();

	//set window.requestAnimationFrame
	(function(w, r) {
		w["r" + r] =
			w["r" + r] ||
			w["webkitR" + r] ||
			w["mozR" + r] ||
			w["msR" + r] ||
			w["oR" + r] ||
			function(c) {
				w.setTimeout(c, 1000 / 60);
			};
	})(window, "equestAnimationFrame");
};

export default {
	luohuaCanvans,
}